I changed the boiler from "on" to "pilot" over the summer. The pilot light is still lit. I went to turn the boiler to "on" today, and set the zones to call to heat. There is no water moving through the system at all - no familiar gurgle - and the sheet metal chimney is not even warm. I don't know a lot about this at all, as it was sort of my ex-husband's thing. Am I missing something or there something else I should be doing?